1. Field of the Invention
This invention relates to a data recording method and apparatus, a data record (recording/recordable/recorded) medium and a data reproducing method and apparatus employed with advantage for compressing and time-divisionally multiplexing digital moving picture data and digital speech data and for recording/reproducing the data on or from, for example, an optical disc.
2. Description of the Related Art
In video works, such as motion pictures, there are occasions wherein plural works having basically the same contents and slightly different in details, that is different in version, under variable circumstances. For example, a so-called directors cut edition, later edited by a director, may exist in addition to the first edition shown in a theater. Specifically, although part of the photographed scenes are cut or modified in the first edition from reasons related to management or under political or cultural backgrounds, these cut or modified scenes may be revived in re-editing for taking changes in the backgrounds or the author's intentions into account. These are identified as director's cut editions, complete editions, special editions and so forth. Three or more different versions may be occasionally derived from one and the same work.
In addition to the versions for showing in a theater, an original work may be edited for matching to the broadcasting time for e.g., television broadcasting or matching to a recording/reproducing apparatus of relatively short play time for household entertainment.
In addition, motion pictures or video works shown for indefinite audience are designated for being shown only for adults (rating). The rating is voluntarily applied by the maker to a motion picture for prohibiting the nonage from viewing it if the motion picture includes inappropriate expressions for nonage. Similarly, a rated video disc, for example, is prohibited from being sold or assigned to the nonage.
The rating in US is not provided by law but is a voluntary process followed by the maker inclusive of the distributer and seller. According to a literature "THE MOVIE BUSINESS BOOK", pp.396 to 406, "THE VOLUNTARY MOVIE RATING SYSTEM", the motion picture is classed into five categories, namely G (General Audiences; All Ages Admitted), PG (Parental Guidance Suggested); some material may not be suitable for children); PG-13 (Parents Strongly Cautioned, Some material may be inappropriate for children under 13; R (Restricted, under 17 requires accompanying parent or adult guardian); and NC-17 (No Children under 17 admitted).
Therefore, under these designations, admittance to a theater or the sale of video tapes or the like is restricted. Heretofore, a sole rating level is set for a given motion picture and referred to in a theater or a video shop for taking the age of the admitted or purchasing persons into account. In contrast to these voluntary process, there is also an idea of compulsorily prohibiting a rated video disc from being viewed by the nonage on the side of a reproducing apparatus. In this case, a flag for discriminating the possible rating is written on a video disc for detection by the reproducing apparatus for prohibiting reproduction. This function is termed a rating system, referred to hereinafter simply as rating.
In an European digital broadcasting system, there is a description "Parental Rating" in the definition of the service information. This broadcasting system provides a method for describing the age based on which the rating is allowed to come into operation by a receiving apparatus. In the above-mentioned rating system, if only a certain scene in a program is objectionable, an identification code is recorded at a position directly before the program starting. If the reproducing apparatus is in a rating mode, this identification code is read and the program is discontinued without being reproduced. In this case, the program in its entirety cannot be viewed.